SCIG12440 - Reaching agreement on income or profit addition: Tax treatment: Extracted income or profits of a sole trader
Money, goods or services improperly taken by a sole trader should invariably be regarded as additional income or profits, see BIM33630. This should apply whether they are taken for the individual’s own use or for family members. (This text has been withheld because of exemptions in the Freedom of Information Act 2000)
Unexplained money etc. in the hands of a sole trader, accepted as derived from income or profits, should be regarded as income or profits of the known source except where the taxpayer is able to show conclusively that it comes from some other source or venture.

